Keller Breland and Marian Breland trained pigs to pick up large wooden dollars and deposit them in a piggy bank. Later the pigs would revert to their natural behavior—dropping the coin, pushing it with their snouts as pigs are prone to do, picking it up again, and then repeating the sequence—delaying their food reinforcer. The Brelands referred to the reason for this behavior as:

Instinctive drift

Explanation:

According to a different source, these are the options that come with this question:

This is an example of instinctive drift. Instinctive drift refers to a tendency that an animal has to revert to its automatic or instinctual behaviour. Because of this tendency, the success of operant conditioning can be limited. When this happens, the learning of an animal during conditioning disappears, and the animal goes back to its original behaviour. This is the case of the pigs in this example.

my man just wants some puu

explanation:

the article must be ratified by three-fourths (38) of states within a proscribed deadline.

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